Printed circuit switch



Oct. 22, 1957 R. E. HARTSOCK PRINTED CIRCUIT SWITCH Filed Feb. 7, 1957 m0 w m y E. U E w e prraz/vfys United States Patent 6 PRINTED CIRCUITSWIT CH' Robert E. Hartsock, La Habra, Califl, assignor to PatentManagement Incorporated, Minneapolis, Minn., a corporatlon of CaliforniaApplication February 7, 1957, SeriaLNo. 638,799

7 Claims. (Cl. 200-44) This inveniton relates to an electrical switchparticularly adapted for use in connection with'printed circuits.

It has been common practice heretofore in designing switches for printedcircuits to placevarious sets of conductor segments in concentriccircles and to make contact with the sets of segments :byamultiplerotating brush system whose center of rotation is-cOincidentwith thecommon center of the concentric setsof conductor segments. This systemhas certain disadvantages. One is that the position of the brushon theinnermost circle or arcuate set of conductor segments becomes verycritical because the arcuate movement isvery small from contact tocontact. Furthermore, on theouter segments or'sets of segments a greatdeal of space is wasted due to the amount of motion necessary to go fromone contact segment to the next. Also, these concentric arcs or circlesmay have enough electrostatic or inductive coupling between them to makeperformance unsatisfactory in either low level or highfrequency-circuits. A further disadvantage' is that if a large number ofswitch circuits is required, such a switch unit takes up anabnormallylarge amount of space due to the inefiicient use of the space on theouter sets of segments.

The present invention is concerned with the design of a switch inwhichthe circuits or parts thereof are no longer connected'to sets ofsegments on concentric circles but are connected to sets of conductorsegments on individual non-concentric circles orarcs. It contemplatesthat the curvature of the two or more arcs of-the arcuately arrangedsets of segments or circles be uniform and consequently the sameaccuracy of brush position is obtained on all circuits. This accurarcyis determined by the diameter of the circle or arc and electrostaticand'inductive coupling may be controlled either by spacing between thevarious circuits or through the use of shielding.

Where the number of circuits required is of the order of or more, forexample, a definite reduction in the size of the plate maybe made sinceeach circuit requires the same area on the plate as distinguished fromthe steadily increasing circle or are diameters of the former concentricarrangement. By way of illustration, as many as-forty-nine 12-positioncircuits have been placed on one side of a panel 8 inches square. Theconcentriccircle type of-switch with the same number of circuits andpositions would require on the order of a 12 inch diameter circle toobtain the same degree of accuracy.

It is a general object of the invention to provide a switch toaccomplish the results outlined above.

Another object of the invention is to provide simple and efiicient meansfor guiding the movable contact panel relative to the printed circuitwith its sets of arcuately or circularly arranged conductor segments.

A further object of the invention is to provide a simply constructed andsmoothly operating actuator for the movable switch panel.

Still a further object of the invention is to provide means wherebyfixed connections can be made from portions of the printed circuit tothe movable switch panel.

Patented Oct. 22, 1957 Other objects=and advantages of the inventionwill more fully-appear from the following description in connectionwiththe accompanying drawing.

Fig. 1 is-a rear elevational view ofan embodiment of the'inventi'on witha portion of the switch-panel broken away to show theunderlying printedcircuit.

Fig. 2 is a section taken approximatelyon 'theline 22 of Fig. l. 1

Fig. 3 is an enlarged fragmentary sectional detail through one of theresilient brush contacts.

In thedrawing there is shown" a relatively stationary panel 6 of adielectric material which carries a printed circuit of conventionaltype. Portions .of the circuit are shown in Fig. 1. They include sets ofcircularly or'arcuately arranged conductor segments, the sets beingdesignated 8, 10-and 12. The set'of segments 10 includes individualsegments 14 and .16. For purposes of illustration the segment 14-has-aconductor 18 connected thereto and segment 16 has a conductor 20connected thereto. Obviously various circuit arrangements can be used.

Located closely adjacent the printed circuit panel '6 is a movableswitch panel 22having. a plurality of circular apertures 24. Extendingfrom the printed circuit panel 6 are pins26 which in Fig.. 2 are shownto have an intermediate flange 28 and an-endfiange 30. The pins 26extend through the apertures 24 in the switch panel 22 and the flanges28 and 30 lie' at opposite sides of the switch .panel 22 -so that saidswitch panel is held against movement toward and away from the printedcircuitpanel 6 yet is capable of movement in a circular path defined bythe edges of the apertures 24 as they bear against thepins 26.

Mounted on the opposite side of the printed circuit panel from theswitchpanel 22-is abracket 32. A shaft 34 extendsthrough the bracket,the printed circuit panel 6 and through anenlarged circular aperture 36in the switch panel 22. Where the shaft 34 passes through the switchpanel it isprovided with an eccentrically mounted disc 38 secured to aflanged sleeve 40 by means of screws 42 as shown in Fig. 1. The flangedsleeve is-secured to the shaft 34 by a set screw 44. At the outer faceof the-printed circuitpanel 6a collar 46 is secured to the shaft 34 anda second collar 48 is mounted on said shaft at the inner face of thebracket 32. That portion of the shaft which extends outwardly of thebracket 32 is provided with a suitable operating knob 50 whichrnay-carryan indicating pointer 52.

Extending between the sets of'arcuate or circular contact segments 8 andHis a conductor 54 which is carried by the movable switch panel 22. Thisconductor has one end thereof shown in detail in Fig. 3. Each endisanchored by any suitable means such as solderingin a tubularsocket56-which extends through the switch. panel 22 and is provided witha contact head 58 adapted to successively engage the individual segmentsof the sets 8 and 10. A small leaf spring 60 is bowed between thecontact-head 58 and the adjacent face ofthe switch panel 22 so that thehead 58will be held in yielding frictional engagement with the conductorsegments of the sets 8 and 10. Consequently, when the knob 50, shaft 34and eccentric 38* are rotated as a unit, and the switch panel 22 islikewise moved in a circular path, guided by the guide pins 26 in theapertures 24, the heads 58 of the movable contacts on the switch panelat the ends of the conductor 54 will engage successive segments of thearcuately or circularly arranged sets of segments 8 and 10. The circularset of conductor segments 12 is shown provided with a yielding brushcontact arrangement 62 at one end of a conductor 64 in the same manneras the two ends of the conductor 54. How ever, the other end of theconductor 64 is not supported by the switch panel 22 but extends througha circular aperture 66 in the switch panel to a fixed connection 68 onthe printed circuit panel 22. The circular aperture 66 is of such sizethat the switch panel 22 can be moved through its circular path by theknob 50 and the edges of said aperture will clear the end of theconductor 64 which is connected to the printed circuit panel 22.

From the foregoing it will be seen that I have provided a switchparticularly adapted for printed circuits which is simple inconstruction and easy to operate. However, its principal advantage liesin the ability to provide a multiplicity of arcuately or circularlyarranged sets of stationary contact or circuit segments such as the sets8, and 12, which are of a common diameter or curvature. As mentionedabove, this eliminates the need for correlating the arcuate brushmovements and segment spacings of the former type of multiple switcharrangement wherein the sets of segments were arranged on concentricarcs or circles. Furthermore, as stated above it is possible to place amuch larger number of individual switch units or sets of segments in agiven panel space. It can readily be seen that a considerably largernumber of sets of segments can be included on the panel 6 shown in thedrawing and where circuit requirements permit, all of the segments canbe of uniform size and shape. With the other type mentioned herein,where a number of concentric sets are used, if it were desired to holdcontact on the innermost set and the outermost set for the same periodof time, the segments of the outermost set would have to beproportionally larger in arcuate extent and would take up a great dealmore space than in the arrangement disclosed herein.

It shoud, of course, be understood that various changes can be made inthe form, details, arrangement and proportions of the various partswithout departing from the spirit of the invention.

I claim:

1. An electrical switch for use in conjunction with sets of arcuatelyarranged conductor segments having contact faces located about difierentcenters, comprising a movable switch member adapted to be placedadjacent said conductor segments, guide means for the switch memberconfining movement of said member to a plane parallel to the adjacentcontact faces of the conductor segments, said guide means confining themovement of the switch member in said plane to an arcuate pathcomparable to the arcs of said arcuately arranged conductor segments,and switch contacts on said switch member positioned to sweep saidarcuately arranged conductor segments.

2. An electrical switch for use in conjunction with sets of arcuatelyarranged conductor segments having contact faces located about differentcenters, a movable switch member adjacent said conductor segments,arcuate guide paths carried by said switch member whose arcs arecomparable to the arcs of said sets of conductor elements and offsettherefrom radially, relatively stationary guide elements positioned inthe guide paths of said switch member, and switch contacts on saidswitch member positioned to sweep said arcuately arranged conductorsegments upon movement of the switch member.

3. In an electrical switch, a panel having sets of arcuately arrangedconductor segments carried thereby, a switch member having arcuate guidepaths carried thereby and in' ofiset relationship to said sets ofconductor segments on said panel, relatively stationary guide elementssupported by said panel and having portions thereof located respectivelyin said arcuate guide paths of said switch member, and switch contactson said switch member positioned to sweep said arcuatelyarrangedconductor segments.

4. In an electrical switch, a panel having sets of arcuately arrangedconductor segments carried thereby, a relatively movable switch panel,means interconnecting the two panels for relative movement of the switchpanel in a plane parallel to that of said first mentioned panel, and aswitch panel actuator having a connection with said switch panel formoving the same in an arc corresponding to those of said arcuatelyarranged conductor segments, and switch contacts on said switch panelpositioned to sweep said arcuately arranged conductor segments.

5. In an electrical switch, a support, sets of arcuately arrangedconductor segments carried by said support and lying on diiferentcenters, a switch panel lying closely adjacent said arcuately arrangedconductor segments and having arcuate guide paths carried thereby onarcs com parable to those of said sets of conductor segments but offsetradially relatively to said conductor segments, switch panel guide meanscarried by said support and having portions thereof engaging the guidemeans of said switch panel, whereby the switch panel can be moved in asingle plane on an arcuate path comparable to the arcs of said sets ofconductor segments, and resilient switch contacts on said switch panelpositioned to sweep said arcuately arranged conductor segments inresilient contact therewith. V V

6. In an electrical switch, a support, an electrical circuit carried bysaid support and including sets of arcuately arranged conductor segmentslocated about difierent centers, a switch panel located closely adjacentsaid support and connected thereto for movement through an arcuate pathcomparable to the arcs of said sets of arcuately arranged conductorsegments, switch contacts on said switch panel positioned to sweep saidarcuately arranged conductor segments, said switch panel having anaperture therethrough with its edge on an are comparable to those ofsaid sets of arcuately arranged conductor segments, and a flexibleconductor extending through said aperture in said switch panel andhaving its ends connected between a point on said switch panel and aportion of said circuit carried by said support.

7. In an electrical switch, sets of arcuately arranged conductorsegments located about different centers, a switch panel locatedadjacent said sets of conductor segments, an actuator for said switchpanel comprising a crank which will move said switch panel on an arccomparable to the arcs of said sets of conductor segments, and switchcontacts on said switch member positioned to sweep said arcuatelyarranged conductor segments.

References Cited in the file of this patent UNITED STATES PATENTS1,799,438 Philbrick Apr. 7, 1931 1,894,645 Trogner Jan. 17, 19332,661,404 Wasserman n Dec. 1, 19 53

